You always get what you pay for. Cold air intake gives you very limited gains. It only works well in conjunction with other mods. It is cheap though. Makes more noise than power, sometimes leeches power from your car if your system isn't balanced.To get the most bang for your buck change out your headers for an aftermarket set. Then change out your exhaust piping and add the intake. Cam sprocket to advance your timing.Suspension will have an effect on your launches and your traction during autocrossing. Lower is not necessarily better on a Honda Civic. Stiffer suspension and stiffer chassis will allow you to roll around corners harder. Wider rubber on the wheels. If you drop your car make sure your wheel camber angles are properly set or you'll break traction easily on launch.Speed in a sport compact import is a function of dollars. But in the end, unless you spend some serious dollars, a Honda Civic is not a fast car. So don't be overzealous and spend thousands of dollars on mods to make it go almost as fast as a better car.